ASoC: Add dmaengine PCM helper functions

This patch adds a set of functions which are intended to be used when
implementing a dmaengine based sound PCM driver.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Vinod Koul <vinod.koul@linux.intel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 49 insertions, 0 deletions

diff --git a/include/sound/dmaengine_pcm.h b/include/sound/dmaengine_pcm.h
new file mode 100644
index 000000000000..a8fcaa6d531f
--- /dev/null
+++ b/include/sound/dmaengine_pcm.h
@@ -0,0 +1,49 @@
+/*
+ *  Copyright (C) 2012, Analog Devices Inc.
+ *      Author: Lars-Peter Clausen <lars@metafoo.de>
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under  the terms of the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the License, or (at your
+ *  option) any later version.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+#ifndef __SOUND_DMAENGINE_PCM_H__
+#define __SOUND_DMAENGINE_PCM_H__
+
+#include <sound/pcm.h>
+#include <linux/dmaengine.h>
+
+/**
+ * snd_pcm_substream_to_dma_direction - Get dma_transfer_direction for a PCM
+ *   substream
+ * @substream: PCM substream
+ */
+static inline enum dma_transfer_direction
+snd_pcm_substream_to_dma_direction(const struct snd_pcm_substream *substream)
+{
+        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+                return DMA_MEM_TO_DEV;
+        else
+                return DMA_DEV_TO_MEM;
+}
+
+void snd_dmaengine_pcm_set_data(struct snd_pcm_substream *substream, void *data);
+void *snd_dmaengine_pcm_get_data(struct snd_pcm_substream *substream);
+
+int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
+        const struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config);
+int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd);
+snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream);
+
+int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
+        dma_filter_fn filter_fn, void *filter_data);
+int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream);
+
+struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream);
+
+#endif